Locked coil cable and method of making same



June 15, 1965 J. J. GRIMES EIAL LOCKED COIL CABLE AND METHOD OF MAKING SAME Filed April 22, 1963 INVENTORS. JOHN J. GR/MES JR, W/LBERT A. LUCHT and RICHARD 7C WOODBURY Attorney United States Patent New Jersey Filed Apr. 22, 1963, Ser. No. 274,488 8 Claims. (Cl. 57-145) This invention relates to a locked coil cable and to a method of making the same. As used hereinafter the term locked coil cable will include one-half locked cable as well as full locked cable. Such cables are shown on pages 111 and 112 of United States Steel Corporations 1959 Catalogue entitled Wire Rope Handbook for Western Wire Rope Users. Locked Wires taken from used rope often show fretting or pitting on the underside as a result of the extreme pressures obtained in service. It is common to lubricate the wires of a locked coil cable during the stranding operation, but this is not always eiiective to prevent damage. The outer wires of a locked coil cable tend to spring apart when cut and also tend to separate from the wires immediately therebeneath. We have found that the springing apart and tendency to separate can be eliminated by stress relieving the outer Wires after the cable is made. However, this normally destroys the lubricant'which is on the cable so that with lubricants normally used for this purpose it would be necessary to add a lubricant to the cable after formation. Since the wires are in such tight formation this is practically impossible to do effectively.

It is therefore an object of our invention to provide a locked coil cable in which the outer wires are stress relieved and a lubricant is provided on the inner surfaces of the locked wires.

Another object is to provide a method of making such a cable.

These and other objects will be more apparent after referring to the following specification and attached drawings, in which:

FIGURE 1 is a cross sectional view of a locked coil cable made according to our invention;

FIGURE 2 is a view, similar to FIGURE 1, showing a half locked cable made according to our invention; and

FIGURE 3 is a schematic view of a standard stranding machine as modified to carry out the method of our invention.

Referring more particularly to FIGURE 1 of the drawings, reference numeral 2 indicates a center wire surrounded by six wires 4 which in turn are surrounded by twelve wires 6. Six wires 8 are arranged in the valleys between wires 4 and 6. A layer of eighteen wires surrounds the wires 6 and a layer of wires 12 surrounds the wires 10. A layer of key wires 14 surrounds the layer of wires 12 and in turn is surrounded by a layer of key wires 16. An outer layer of lock wires 18 surrounds the key wires 16.

In making up the locked coil cable shown the wires 2, 4, 6 and 8 are first stranded together with a right lay. Then, in separate operations, wires 10 are stranded over the wires 6 with a right lay, wires 12 are stranded over the wires 10 with a right lay, wires 14 are stranded over the wires 12 with a left lay, wires 16 are stranded over the wires 14 with a right lay, and wires 18 are stranded over the wires 16 with a left lay. This is the conventional way of making locked coil cables.

According to our invention it is preferred that the process wire from which the wires 14, 16 and 18 are drawn be first coated with a material which acts as a base for the wire drawing lubricant. This is preferably zinc phosphate, but could be any of the other well known "ice wire drawing bases suitable for this purpose such as iron phosphate, borax, lime, iron oxalate and silicates. The base material acts as a carrier for the lubricant, causes adherence to the wire, and prevents galling. It must be able to withstand temperatures of between 600 and 1100 F. The process wire is preferably immersed in a solution of this base material and the drawing lubricant applied thereover. The lubricant consists of between 5 and 30% by volume of M05 and the remainder any of the well known wire drawing lubricants, such as calcium stearate, and any of the well known fillers such as lime. Graphite, silicone, phosphates, or a mixture of potassium phosphate and sodium tetraborate as disclosed in Luckerath Patent No. 2,990,610, dated July 4, 1961 may be substituted for the M05 After drawing to size, the wires are stranded in the manner described above in a standard wire strand.- ing machine or machines. However, a lubricating mixture is applied to the wires 14, 16 and 18 over the base coating during the stranding operation. The lubricating mixture includes any of the well known wire rope lubricants to which are added other materials or lubricants which resist high temperatures such as M08 graphite, silicone, phosphates, or a mixture of potassium phos phate and sodium tetraborate as disclosed in Luckerath Patent No. 2,990,610, dated July 4, 1961. In general these Wire rope lubricants have an asphaltic or petroleum type base and are not ordinarily soluble in water but are soluble in kerosene or any of the other lighter hydrocarbons. The lubricants must not break down in the presence of acid fumes, but must be acid free so as not to corrode the wires. While the flash point may vary somewhat it is generally between 400 and 500 F. The Saybolt Furol viscosity of typical lubricants at 210 F. may be a maximum of 600 to 800 and at 250 F. a maximum of between and 150. Suitable lubricants used by the American Steel and Wire Division of United States Steel Corporation are marketed by such companies as Cities Service Oil Company and The Texas Company. Their trade names for these lubricants are Cities Service -X and Texaco C. The final stranding operation is done in the apparatus of FIGURE 3 wherein a standard strander 20 is shown. As the wires 13 are stranded around the Wires 16 the lubricating mixture described above is added through a pipe 22 at the point of twist before entering closing die 24 to form the cable C. A preferred lubricating mixture contains 5% by volume of M08 However, the weight of the M08 graphite, silicone, phosphates, or a mixture of potassium phosphate and sodium tetraborate as disclosed in Luckerath Patent No. 2,990,610, dated July 4, 1961, may be between 5 and 30% of the total mixture. From the closing die 24 the cable C is fed through a conduit 26 which has an inlet 23 for nitrogen or other inert gas. Cable C is heated by means of an induction coil 30 which surrounds the conduit 26. Depending upon the type of steel used in the cable C the temperature to which the wires 14, 16 and 18 is heated will vary between 600 and 1100 F. The higher temperatures will be used with stainless steel. Immediately after leaving the conduit 30 the lock wires 18 are quenched by passing through a water spray 32. The cable then passes around a capstan 34 to a reel 36. It is preferred that only sufiicient tens-ion be applied to the cable between the strander 20 and capstan 34 to keep it taut. It is preferred that the induction coil 30 be of such length and the power supplied be such that only the wires 14, 16 and 18 be heated to the stress relieving temperature.

Referring now to FIGURE 2, reference numeral 38 indicates the round core wires of a half locked cable C. These wires are stranded together in the usual manner to form the core. Round outer wires 40 and lock wires 42 are stranded therearound in the usual manner. The

wires 40 and 42 are drawn using the same base coating and lubricant as with the wires 14, 16 and 18. The outer wires 40 and 42 will be applied by the apparatus of FIG- shown and described it will be apparent that other adaptations and modifications may be'made without departing from the scope of the following claims,

We'claim: 2

1. A lock coil cable comprising a core, outer stress .relieved steel lock wires surrounding said core, a base coating of a wire drawing aid on said lock wires, .and an outer coating of a wire rope lubricating mixture capable of resisting temperaturesof at least 600 F. over said base coating, said wire rope lubricating mixture including ,a wire rope lubricant and a, wiredrawinglubricant. 2. A lock coil cable according to claim 1 in which the base coating is zinc phosphate and the outer coatingincludes a mixture of from 5 to 30% by volume of molydisulphide and a wire rope lubricant.

3. A lock coil cable according to claim 1 including key wires directly beneath the lock wires, a base coating of va wire drawing aid on said key wires, and an outer coating of a wire rope lubricating mixture capable of resisting temperatures of at least 600 F. over said base coating,

said last named lubricatingmixture including a wire rope lubricant and a wire drawing lubricant. p v

4. A lock coil cable according to claim 3 in which the base coating f on the key wires is zinc phosphate and the outer coating includes a mixture of from 5 to 30% by volume of moly-disulphide anda wire rope lubricant.

5. The method of making a lock coil cable comprising I stranding steel wires including outer lock wires to form the cable with a base coating of a wire drawing aid on the outer lock wires and an outer coating of a wire rope lubricating mixture capable of resisting temperatures of at least 600 F. over said base coating, and then induction heating at least the outer lock wires to a temperatureof between 600 and 1100 F.

6.;The methodof making a lock coil cable according to claim 5 in which key wires are provided directly beneath the lock wires coated with the same coatings as the lock wires, and the key wires are induction heated to a temperature between 600 and 1100 F.

7. The method of making a lock coil cable which comprises drawing steel wires having a base coating of a wire drawing aid thereon and an outer coating of a wire drawing lubricating mixture including a substance of the class consisting of moly-disulphide, graphite, silicone, phosphates and a mixture of potassium phosphate and sodium tetraborate to a cross section suitable for outer lock wires, stranding wires to form the cable except for the outer lock wires, then stranding the said drawn steel lock wires about the other wires, applying a rope lubricating mixture capable of resisting temperatures ofat least 600 F. to the said drawn steel lock wires during the last named stranding operation, and then induction heating at least the outer lock wires to a temperature of between 600 and 1100 F. v

8.v The method of making a lock coil cable according to claim 7 including the steps of drawing other steel wires in the same lubricating mixture as the lock wires to a key shape, stranding said ,key shape'wir'es together before the said lock wires are strandedtogether,applying a wire rope lubricating mixture capable of resisting temperatures of at least 600 F. to said key Wires as they are stranded together, and heating said key wires to a temperature between 600 and 1100 'F. at the same time as the lock W1res.; 7

References Cited by the Examiner UNITED STATES PATENTS 1,730,741 10/29 Munford e 205-49 1,818,845 8/31' Fessl.. 57-9 1,993,110 3/35 Meyers 57'138X 2,588,234 3/52 Henricks.

2,842,837 '7/58 Huet 29528 2,900,710 8/59 Hurat 29-528 2,990,610 7/61v Luckenrath et a1. 29528 FOREIGN PATENTS 595,245 4/34 Germany- V MERVIN STE IN, Primary Examiner. 

1. A LOCK COIL CABLE COMPRISING A CORE, OUTER STRESS RELIEVED STEEL LOCK WIRES SURROUNDING SAID CORE, A BASE COATING OF A WIRE DRAWING AID ON SAID LOCK WIRES, AND AN OUTER COATING OF A WIRE ROPE LUBRICATING MIXTURE CAPABLE OF RESISTING TEMPERATURE OF AT LEAST 600* F. OVER SAID BASE COATING, SAID WIRE ROPE LUBRICATING MIXTURE INCLUDING A WIRE ROPE LUBRICANT AND A WIRE DRAWING LUBRICANT. 